Potential Protective Role of Melatonin in Benign Mammary Cells Reprogrammed by Extracellular Vesicles from Malignant Cells.

(1) Background: Mammary neoplasms in female dogs share many similarities with the same tumor class in humans, rendering these animals a valuable preclinical model for studying novel therapies against breast cancer. The intricate role of extracellular vesicles (EVs), particularly exosomes, in breast carcinogenesis, by transferring specific proteins to recipient cells within the tumor microenvironment, underscores their significance. Melatonin, a hormone recognized for its antitumor effects, adds another layer of intrigue. (2) Methods: EVs obtained from the plasma of dogs diagnosed with mammary tumors were co cultivated with the benign epithelial lineage E-20 using DMEM. The experiment comprised four 24 h treatment groups: control, EVs, melatonin, and EVs + melatonin. A series of assays were conducted, including colony formation, proliferation, and cellular migration assessments. Furthermore, we conducted colony formation, proliferation, and cellular migration assays. We performed immunohistochemistry for proteins of the mTOR pathway, including mTOR and AKT. (3) Results: Exosomes alone significantly increased proliferation, migration, and colony formation rates and, upregulated the expression of mTOR and AKT proteins. However, when melatonin was added, a protective effect was observed. (4) Conclusions: These findings contributed to the use of melatonin to modulate EV-mediated signaling in the clinical veterinary oncology of mammary tumors.

Decoding Hidden Messengers: Proteomic Profiling of Exosomes in Mammary Cancer Research.

Cancer is a complex and heterogeneous disease, influenced by various factors that affect its progression and response to treatment. Although a histopathological diagnosis is crucial for identifying and classifying cancer, it may not accurately predict the disease's development and evolution in all cases. To address this limitation, liquid biopsy has emerged as a valuable tool, enabling a more precise and non-invasive analysis of cancer. Liquid biopsy can detect tumor DNA fragments, circulating tumor cells, and exosomes released by cancer cells into the bloodstream. Exosomes attracted significant attention in cancer research because of their specific protein composition, which can provide valuable insights into the disease. The protein profile of exosomes often differs from that of normal cells, reflecting the unique molecular characteristics of cancer. Analyzing these proteins can help identify cancer-associated markers that play important roles in tumor progression, invasion, and metastasis. Ongoing research and clinical validation are essential to advance and effectively utilize protein biomarkers in cancer. Nevertheless, their potential to improve diagnosis and treatment is highly promising. This review discusses several exosome proteins of interest in breast cancer, particularly focusing on studies conducted in mammary tissue and cell lines in humans and experimental animals. Unfortunately, studies conducted in canine species are scarce. This emphasis sheds light on the limited research available in this field. In addition, we present a curated selection of studies that explored exosomal proteins as potential biomarkers, aiming to achieve benefits in breast cancer diagnosis, prognosis, monitoring, and treatment.

Metabolic Alterations in Canine Mammary Tumors.

Canine mammary tumors (CMTs) are among the most common diseases in female dogs and share similarities with human breast cancer, which makes these animals a model for comparative oncology studies. In these tumors, metabolic reprogramming is known as a hallmark of carcinogenesis whereby cells undergo adjustments to meet the high bioenergetic and biosynthetic demands of rapidly proliferating cells. However, such alterations are also vulnerabilities that may serve as a therapeutic strategy, which has mostly been tested in human clinical trials but is poorly explored in CMTs. In this dedicated review, we compiled the metabolic changes described for CMTs, emphasizing the metabolism of carbohydrates, amino acids, lipids, and mitochondrial functions. We observed key factors associated with the presence and aggressiveness of CMTs, such as an increase in glucose uptake followed by enhanced anaerobic glycolysis via the upregulation of glycolytic enzymes, changes in glutamine catabolism due to the overexpression of glutaminases, increased fatty acid oxidation, and distinct effects depending on lipid saturation, in addition to mitochondrial DNA, which is a hotspot for mutations. Therefore, more attention should be paid to this topic given that targeting metabolic fragilities could improve the outcome of CMTs.

Liquid biopsy can detect BRCA2 gene variants in female dogs with mammary neoplasia.

Mammary tumours (MT) are one of the most prevalent malignancies in female dogs and women. Currently, molecular analyzes have shown that each tumour type presents its own genetic signature. In this context, liquid biopsy allows a comprehensive genetic characterisation of the tumour, enabling early diagnosis and personalised treatment of patients. In women, deleterious mutations inherited in BRCA2 gene are associated with an increased risk of breast cancer, resistance to therapies and worse prognosis. In female dogs, there are many divergent data on the involvement of BRCA2 gene with mammary carcinogenesis and what its pathogenic potential is. Therefore, the objective was to identify BRCA2 gene variants in 20 plasma DNA samples, from 10 newly diagnosed dogs with mammary cancer (RD), five control (CTR) and five mastectomized patients. Eleven single nucleotide polymorphisms (SNPs) were detected, most of them in the exon 11 and two indels (deletion/insertion) in the BRCA2 gene. However, there was no statistically significant difference in the SNPs/indels detected between the groups. In addition, only one SNP (p.T1425P) and one deletion (p.L2307del) were considered deleterious using in silico computational models. Interestingly, most common variants were present in the plasma of all groups, except for the Ile2614Thr, Ile2614Val, Thr1425Pro and p.L2307del variants. Thus, we observed that SNPs are common in the BRCA2 gene of female dogs with MT, with a similar condition identified in women with breast cancer. Liquid biopsy approach in dogs with MT is useful for genetic and therapeutic proposals.

Immunohistochemical Evaluation of PARP and Caspase-3 as Prognostic Markers in Prostate Carcinomas.

Prostate cancer is the second most common neoplasm among men, with a high mortality rate in advanced stages. Poly (ADP-ribose) polymerase (PARP) plays an important role in repair to DNA damage, being associated with resistance to tumor cell death. Conversely, Caspase-3 is a crucial mediator of programmed cell death, being highly expressed in apoptotic cells. The aim of the present study was to characterize the expression of PARP and Caspase-3 by immunohistochemistry in patients with advanced prostate cancer. PARP and Caspase-3 were independently correlated to patients' evolution, in accordance with the classification of prognostic groups. The increase in PARP expression was positively correlated with tumor patients with poor prognosis (P < 0.0001). In contrast, a decrease in Caspase-3 expression was identified in patients with poor prognosis, when compared with prostate cancer patients with good prognosis (P = 0.0007). Numerically, 92.3% of patients previously classified with poor prognosis showed higher PARP expression, while 93.75% of patients previously classified with good prognosis showed higher levels of Caspase-3. We conclude that PARP and Caspase-3 are potential prognostic markers for prostate cancer patients with different prognosis.

Liquid Biopsy as a Diagnostic and Prognostic Tool for Women and Female Dogs with Breast Cancer.

INTRODUCTION: Breast cancer (BC) is the malignant neoplasm with the highest mortality rate in women and female dogs are good models to study BC. OBJECTIVE: We investigated the efficacy of liquid biopsy to detect gene mutations in the diagnosis and follow-up of women and female dogs with BC. MATERIALS AND METHODS: In this study, 57 and 37 BC samples were collected from women and female dogs, respectively. After core biopsy and plasma samples were collected, the DNA and ctDNA of the tumor fragments and plasma were processed for next generation sequencing (NGS) assay. After preprocessing of the data, they were submitted to the Genome Analysis ToolKit (GATK). RESULTS: In women, 1788 variants were identified in tumor fragments and 221 variants in plasma; 66 variants were simultaneously detected in tumors and plasma. Conversely, in female dogs, 1430 variants were found in plasma and 695 variants in tumor fragments; 59 variants were simultaneously identified in tumors and plasma. The most frequently mutated genes in the tumor fragments of women were USH2A, ATM, and IGF2R; in female dogs, they were USH2A, BRCA2, and RRM2. Plasma of women showed the most frequent genetic variations in the MAP3K1, BRCA1, and GRB7 genes, whereas plasma from female dogs had variations in the NF1, ERBB2, and KRT17 genes. Mutations in the AKT1, PIK3CA, and BRIP genes were associated with tumor recurrence, with a highly pathogenic variant in PIK3CA being particularly prominent. We also detected a gain-of-function mutation in the GRB7, MAP3K1, and MLH1 genes. CONCLUSION: Liquid biopsy is useful to identify specific genetic variations at the beginning of BC manifestation and may be accompanied over the entire follow-up period, thereby supporting the clinicians in refining interventions.

Melatonin-Loaded Nanocarriers: New Horizons for Therapeutic Applications.

The use of nanosized particles has emerged to facilitate selective applications in medicine. Drug-delivery systems represent novel opportunities to provide stricter, focused, and fine-tuned therapy, enhancing the therapeutic efficacy of chemical agents at the molecular level while reducing their toxic effects. Melatonin (N-acetyl-5-methoxytriptamine) is a small indoleamine secreted essentially by the pineal gland during darkness, but also produced by most cells in a non-circadian manner from which it is not released into the blood. Although the therapeutic promise of melatonin is indisputable, aspects regarding optimal dosage, biotransformation and metabolism, route and time of administration, and targeted therapy remain to be examined for proper treatment results. Recently, prolonged release of melatonin has shown greater efficacy and safety when combined with a nanostructured formulation. This review summarizes the role of melatonin incorporated into different nanocarriers (e.g., lipid-based vesicles, polymeric vesicles, non-ionic surfactant-based vesicles, charge carriers in graphene, electro spun nanofibers, silica-based carriers, metallic and non-metallic nanocomposites) as drug delivery system platforms or multilevel determinations in various in vivo and in vitro experimental conditions. Melatonin incorporated into nanosized materials exhibits superior effectiveness in multiple diseases and pathological processes than does free melatonin; thus, such information has functional significance for clinical intervention.

Exosomes and Melatonin: Where Their Destinies Intersect.

Cell-to-cell communication is a broad and complex process associated with regular stimuli to maintain healthy cell interactions. One of the agents capable of cellular communication is known as an exosome, a subset of extracellular vesicles (EVs) released by the cell membrane. The exosome contains a wide range of functional proteins, mRNAs and miRNAs, which have the potential to interact with healthy or diseased cells in the body. On the other hand, melatonin also acts as a cellular communicator, produced and released by the pineal gland in a circadian way and also, non-circadian melatonin is derived from the mitochondria of all normal cells. In addition to exhibiting antioxidant, anti-inflammatory, anti-tumor and anti-aging activities, melatonin has recently been studied by its influence on exosomes. This review summarizes the relationship between exosomes and melatonin in various pathological processes. There is robust evidence that their combination ameliorates inflammation, ischemia-reperfusion injury, hepatic metabolic disturbance, cancer immunosuppression status, degenerative processes like chronic kidney disease, vascular calcification, ageing, ischemic brain injury, neurodegenerative diseases, obesity, colitis, wound healing and even embryonic development. Association of exosomes and melatonin represent a promising therapeutic tool, capable of interfering with basic molecular processes, such as oxidative stress and the inflammatory cascade, which support many pathophysiological aspects of diseases.

DEA 1. 1 blood group frequency in dogs attended at the veterinary hospital of UFMT (Sinop/MT), risk of DEA 1 negative dog sensitization and occurrence of hemolytic transfusion reaction in a second blood transfusion / Frequência do grupo sanguíneo DEA 1. 1 em cães atendidos no Hospital Veterinário da UFMT (Sinop/MT), risco de sensibilização de cães DEA 1 negativos e da ocorrência de reação transfusional hemolítica por ocasião de uma segunda transfusão de sangue

The goal of this research was to identify the frequency of the DEA 1.1 blood group in dogs from Sinop, Mato Grosso, Brazil, to help in the recruitment of compatible blood donors and recipients, and to assess the risk of transfusion reactions in previously sensitized dogs. Also, from the obtained results, to pick potential blood donors to compose a data bank. 195 adult dogs (1 to 4 years old), males and females, mongrel and purebred dogs were screened at the Veterinary Hospital of the University of Mato Grosso. The DEA 1.1 blood typing was performed using commercially available immunochromatographic strip for DEA 1.1 (Quick Test DEA 1.1, Alvedia, Lyon, France). The results showed a general frequency of 65% for DEA 1.1 positive dogs (n = 126) and 35% for DEA 1 negative dogs (n = 69). The general risk of sensitization of a DEA 1 negative dog following a first transfusion with DEA 1.1 positive blood was 23%, while the risk of this sensitized recipient to receive DEA 1.1 positive blood in a second transfusion and to develop an acute hemolytic reaction was calculated to be 5%. The blood typing of the dogs allowed their classification as DEA 1 typed blood donors, in a preliminary data bank, and also ensured the safety of blood transfusions.

Objetivou-se identificar a frequência do grupo sanguíneo DEA 1.1 em cães de Sinop, Mato Grosso, Brasil, para auxiliar a seleção de doadores e receptores de sangue compatíveis e, adicionalmente, avaliar o risco de reações transfusionais em cães sensibilizados. Além disso, a partir dos resultados obtidos, selecionar potenciais doadores de sangue para compor um banco de dados. Um total de 195 cães adultos (de 1 a 4 anos de idade), machos e fêmeas, mestiços e puros, que nunca haviam recebido transfusões de sangue, foram triados no Hospital Veterinário da Universidade do Mato Grosso. A tipagem sanguínea DEA 1.1 foi realizada utilizando-se ensaio imunocromatográfico comercialmente disponível para DEA 1.1 (Quick Test DEA 1.1, Alvedia, Lyon, França). Os resultados demonstraram uma frequência geral de 65% para cães DEA 1.1 positivos (n = 126) e 35% para cães DEA 1 negativos (n = 69). O risco geral de sensibilização de cães DEA 1 negativos após uma primeira transfusão com sangue DEA 1.1 positivo foi calculado em 23%, enquanto o risco deste receptor sensibilizado receber sangue DEA 1.1 positivo em uma segunda transfusão e desenvolver uma reação hemolítica aguda foi calculado em 5%. A tipagem sanguínea dos cães permitiu sua inserção como doadores de sangue tipados para o grupo DEA 1 em um banco de dados preliminar e garantiu a segurança das transfusões de sangue.

Frequência do grupo sanguíneo DEA 1.1 em cães atendidos no Hospital Veterinário da UFMT (Sinop/MT), risco de sensibilização de cães DEA 1 negativos e da ocorrência de reação transfusional hemolítica por ocasião de uma segunda transfusão de sangue / DEA 1.1 blood group frequency in dogs attended at the veterinary hospital of UFMT (Sinop/MT), risk of DEA 1 negative dog sensitization and occurrence of hemolytic transfusion reaction in a second blood transfusion

Objetivou-se identificar a frequência do grupo sanguíneo DEA 1.1 em cães de Sinop, Mato Grosso, Brasil, para auxiliar a seleção de doadores e receptores de sangue compatíveis e, adicionalmente, avaliar o risco de reações transfusionais em cães sensibilizados. Além disso, a partir dos resultados obtidos, selecionar potenciais doadores de sangue para compor um banco de dados. Um total de 195 cães adultos (de 1 a 4 anos de idade), machos e fêmeas, mestiços e puros, que nunca haviam recebido transfusões de sangue, foram triados no Hospital Veterinário da Universidade do Mato Grosso. A tipagem sanguínea DEA 1.1 foi realizada utilizando-se ensaio imunocromatográfico comercialmente disponível para DEA 1.1 (Quick Test DEA 1.1, Alvedia, Lyon, França). Os resultados demonstraram uma frequência geral de 65% para cães DEA 1.1 positivos (n = 126) e 35% para cães DEA 1 negativos (n = 69). O risco geral de sensibilização de cães DEA 1 negativos após uma primeira transfusão com sangue DEA 1.1 positivo foi calculado em 23%, enquanto o risco deste receptor sensibilizado receber sangue DEA 1.1 positivo em uma segunda transfusão e desenvolver uma reação hemolítica aguda foi calculado em 5%. A tipagem sanguínea dos cães permitiu sua inserção como doadores de sangue tipados para o grupo DEA 1 em um banco de dados preliminar e garantiu a segurança das transfusões de sangue.

The goal of this research was to identify the frequency of the DEA 1.1 blood group in dogs from Sinop, Mato Grosso, Brazil, to help in the recruitment of compatible blood donors and recipients, and to assess the risk of transfusion reactions in previously sensitized dogs. Also, from the obtained results, to pick potential blood donors to compose a data bank. 195 adult dogs (1 to 4 years old), males and females, mongrel and purebred dogs were screened at the Veterinary Hospital of the University of Mato Grosso. The DEA 1.1 blood typing was performed using commercially available immunochromatographic strip for DEA 1.1 (Quick Test DEA 1.1, Alvedia, Lyon, France). The results showed a general frequency of 65% for DEA 1.1 positive dogs (n = 126) and 35% for DEA 1 negative dogs (n = 69). The general risk of sensitization of a DEA 1 negative dog following a first transfusion with DEA 1.1 positive blood was 23%, while the risk of this sensitized recipient to receive DEA 1.1 positive blood in a second transfusion and to develop an acute hemolytic reaction was calculated to be 5%. The blood typing of the dogs allowed their classification as DEA 1 typed blood donors, in a preliminary data bank, and also ensured the safety of blood transfusions.